Olympus-OM
[Top] [All Lists]

[OM] Event shooting - postmortem - another one, the focus contest

Subject: [OM] Event shooting - postmortem - another one, the focus contest
From: Chuck Norcutt <chucknorcutt@xxxxxxxxxxx>
Date: Thu, 21 Apr 2005 18:24:08 -0400
Just a small addition to the Schnozz's comments on autofocus and events.

I recently assisted shooting at a bat mitzvah dinner party along with 
two other photographers.  One was shooting with a Canon 10D and the 
other with a Canon D60.  I was shooting with my Minolta A1.

My photo mentor shooting the D60 commented early on that we were in for 
trouble.  The DJ's running the show for the kids are known to keep the 
light level very low.  He was familiar with these guys and knew that all 
of the cameras would have some difficulty focusing.

The first hour or so went OK and even my A1 was able to focus.  Slowly, 
to be sure, but it would eventually lock in if the subject wasn't moving 
too much.  Finally I noticed that the camera couldn't focus at all 
unless I found a nearby bright spot at the same distance as the subject. 
  The DJ's had cut the lights again.

It soon became apparent that the camera just couldn't cut it.  Nor could 
I see well enough to manually focus with that silly EVF.  Finally, I 
decided to do the only thing I could which was to manually focus at 
about 6 feet and hope the depth of field would carry me through.

Much to my surprise, after all the photos were in from all three 
cameras, it was obvious that I and the Minolta A1 had won the focus 
contest.  The A1 delivered the greatest percentage of in-focus images by 
a substantial margin.

I was puzzled at first but then dragged out the DOF calculator and 
finally realized that the DOF for the small, 1/3" sensor on the A1 is a 
lot more than I thought; especially since 50 percent of the shots were 
taken at equivalent focal lengths of 28-55mm.

The E-1, of course, has a larger sensor than the A1 and will have 
shallower depth of field.  But it is still a formidable range.  With the 
14-54 at 14mm and f/8 the hyperfocal distance is 4.87 feet which gives 
DOF from 2.47 feet to infinity.  At 27.5mm (the 55mm equivalent I 
mentioned above) and f/8 focused at 12 feet the DOF extends from 7.3 to 
33.3 feet.  Even with no flash and having to shoot at f/4 will still 
give DOF from 9.1 to 17.7 feet when focused at 12 feet.  I should also 
point out that these figures assume a resolution of 60 lines/mm which 
should be sharp enough to make a good 8x10.  If you want to assume that 
the party picures won't be larger than 4x6 or 5x7 then you can relax 
that assumption for even greater DOF.

I talk about DOF a lot but it took this event to bring it home. 
Shooting digital brings a lot more changes than simply no film.

Chuck Norcutt


==============================================
List usage info:     http://www.zuikoholic.com
List nannies:        olympusadmin@xxxxxxxxxx
==============================================

<Prev in Thread] Current Thread [Next in Thread>
Sponsored by Tako
Impressum | Datenschutz